They had a generally better relations with the Elves than their neighbors in Nogrod, and as well as being responsible for the building of Menegroth. They first met the craft loving Noldor Elves near Mount Rerir and a great friendship began between the two peoples.
they fought bravely beside Elves and Men during the Nirnaeth Arnoediad. Even losing their ruler Lord Azaghâl in battle, to the Dragon, Glaurung.
When the Dwarves of Nogrod built a great host of Dwarves to attack Doriath the Broadbeams tried to dissuade them from war, but they didn't heed their and went on to fight in the Sack of Doriath, and later their demise the Battle of Sarn Athrad. After this tragedy the Belegostians started fleeing to Khazad-dûm, for fear of reprise from the Elves. Their was much loathing between Elf and Dwarf from there on.
Belegost was later ruined in the War of Wrath, and most of the Brodbeams left for Khazad-dum, while some stayed to build, or rebuild new homes and mines, along with some remaining Firebeards from Nogrod.

The Belegostians were second only to the Dwarves of Nogrod in smithing. They learned many secrets in smithing from the Elves, and Elves from the Dwarves. They created many weapons for the Elves when evil began to stir in Beleriand, and Belegost was the first to create linked ring mail. Also the great pearl called Nimphelos was greatly prized by the chieftain of Belegost above a mountain of wealth.

Apparently the the Broadbeams along with the Firebeards, used Khuzdul names instead of names from a different language. Which is odd considering they were secretive about their language and true names. But they probably just used a given name, like Durin's folk used the names of the Northmen.